Non-destructive Examinations are typically performed to inspect the integrity of industrial components such as turbine/generator blades, discs and other components exposed to operational service stress. In particular, non-destructive examinations are conducted in an attempt to mitigate the likelihood of a catastrophic failure due to materials degradation as a result of a component's exposure to its service environment.
Indications of potential future failure, if present in the materials of the component under test, are typically identified and evaluated by a human inspector. In general, the inspector utilizes one or more non-destructive examination methods to obtain inspection data, which includes measurements of the component being inspected. After collecting the data, the inspector must spend considerable amounts of time managing the data. The inspector must also spend considerable amounts of time performing data analysis to ascertain from the collected data, whether there are discontinuities in the material of the component under test. If discontinuities are detected in the component under test, the inspector must then attempt to determine the size and extent of the detected discontinuities to assess the overall integrity of the component. Based upon the inspection results, the inspector may also make assessments as to the expected in-service lifetime of the component.
Performing material discontinuity determinations is not a trivial task. Industrial component inspections require engineering know-how as well as significant amounts of experience inspecting components. Even an experienced inspector with extensive know-how is often required to make assumptions, especially when investigating whether a component exhibits a non-surface discontinuity. As such, common practice dictates incorporating safety factors into the inspection criteria established by the inspector to make a representative assessment of a given component under test. In this regard, a high degree of conservatism and subjectivity is often placed into the component inspection process.